The present invention relates to an interface unit between a user and an electronic device comprising a control logic and a rectangular cathode screen with a scanning facility.
A cathode screen of this nature is scanned by a luminous spot which successively occupies all the points of the screen according to a pre-determined scanning cycle.
The cathode screens usually found are essentially rectangular-shaped and have for example approximately 625 lines on their width and 800 points per line. The luminous spot moves successively on all the points of each line and travels across a line at a scanning speed of 64 micro-seconds for example.
The invention is used in particular for remote controls for controlling the operation of a television or a video recorder. Operation control of these devices by means of the generally found remote controls is fastidious insofar as the command option windows must be successively displayed on the screen so that a user can select one of the operating modes of the television or video recorder.
The object of the present invention is to find a solution to the above drawbacks by creating an interface unit which facilitates simple control of an electronic device and whereby this is achieved by simple, efficient and cost-effective means.
For this purpose, according to the invention an interface unit of the type in question comprises
a control box consisting of:
at least two lighting sensors adapted to the scanning of the screen by the luminous spot:
a lighting sensor D1 which has a detection field comprising at least the upper left section of the screen;
a lighting sensor D2 which has a detection field limited to a reduced zone Z of the screen;
a wide-band amplifier and a high-pass filter for each of the lighting sensors;
means of detection of the appearance of the luminous spot in the detection field of each of the sensors in order to generate a pre-determined logical signal;
means of logical and arithmetical processing of the logical signals in order to calculate the position of the target zone Z on the screen at least on the basis of firstly the instant of appearance of the logical signal corresponding to the lighting sensor D1 whose detection field comprises at least the upper left section of the screen and which corresponds to the beginning of the scanning of the image, and secondly the instant of appearance of the logical signal corresponding to the lighting sensor D2 whose detection field is limited and which corresponds to the passage of the luminous spot in front of the target zone Z;
a transmission chain from the box towards the electronic device, the device having a logic adapted to be modified by the information received,
and wherein the control box is placed at a distance from the cathode screen.
Therefore, owing to its facilities, the interface unit easily facilitates the designation of a point or the selection of an object on a cathode screen at a distance.
In preferred embodiments of the interface unit according to the present invention, one and/or other of the following facilities are also used:
the means of logical and arithmetical processing of the logical signals calculates the position of the target zone Z on the screen on the basis of the time difference between firstly the instant of appearance of the logical signal corresponding to the lighting sensor D1 whose detection field comprises at least the upper left section of the screen and which corresponds to the beginning of scanning of the image, and secondly the instant of appearance of the logical signal corresponding to the lighting sensor D2 whose detection field is reduced and which corresponds to the passage of the luminous spot in front of the target zone Z;
the detection field of the sensor D1 contains the whole screen and the means of logical and arithmetical processing of the logical signals calculate the position of the target zone Z on the screen on the basis, furthermore, of the instant of appearance of the logical signal corresponding to the lighting sensor D1 on a line which also corresponds to the passage of the luminous spot in front of the target zone Z;
the means of logical and arithmetical processing are also capable of:
memorizing the instants of appearance of the logical signals corresponding to the lighting sensor D1 for several lines which correspond to the beginning of the scanning of the screen,
memorizing for several lines of scanning the instants of the signals corresponding to the lighting of the sensors D1 and D2 by the passage of the luminous spot on the same line;
the lighting sensor D1 and the lighting sensor D2 have parallel, close axes;
the lighting sensor D1, whose detection field comprises at least the upper left section of the screen, has a lighting detector and a focusing device in order to improve the sensitivity of the sensor;
the focusing device is chosen from a conical mirror and a system of optical lenses;
the lighting sensor D2, whose detection field is reduced, has a lighting detector and a focusing system in order to focus the light coming from the target zone Z on the active surface of the detector;
in the upper left section, the screen has a portion with a reduced surface, and which is light in color;
the electronic device also has means of controlling the screen in order to display on the screen a graphic effect in a position in relation to the target zone Z;
the control box has means which can be selectively activated by the user, and whereby the result of the action is transmitted to the electronic device by the box;
the selectively activated means of control are chosen among keys, potentiometers, pressure sensors, angle sensors, position sensors, gyroscopes, at least one vocal command and at least one joystick;
the control box transmits information to the electronic device when the position of the target zone Z has changed by a pre-determined minimum value;
the control box also has means of identification adapted so that the electronic device recognizes the control box, whereby these means of identification selectively generate identification data of the box which is sent to the electronic device;
several control boxes communicate with the electronic device and the means of control of the device of each control box transmit their information a certain number of times to the electronic device, in order to increase the probability of the electronic device receiving the information emitted by each box without interference with the information emitted by the other boxes;
several control boxes communicate with the electronic device and the means of control of the device of each control box transmit their information to the electronic device, being synchronised in relation to the beginning of the image displayed on the screen, and at instants defined by intervals specific to each box in relation to the beginning of the image;
the electronic device has means which cause the transmission of new information by at least one of said control boxes;
the means causing the transmission of new information consist in that at least one part of the screen displays a pre-determined sequence of luminous intensities;
the emitter and the receiver communicate by waves;
and the emitter and the receiver are linked by a transmission cable;
the control box has means of measuring and memorizing periodically the lighting time of the sensor D2 by the luminous spot in order to facilitate detection of approaching or distancing of the control box from the screen by the measurement of the variation in the lighting time of the sensor by said luminous spot;
the control box has, firstly, two lighting sensors D2, D3 of parallel, close axes and having detection fields which are each limited to a reduced zone Z, Zxe2x80x2 of the screen and, secondly, supplementary means of logical and arithmetical processing in order to measure the position of the two distinct zones Z, Zxe2x80x2 on the screen and to facilitate the calculation of the rotation angle of the control box in relation to the common axis of said lighting sensors D2, D3.